Pavement structure



y 12, 1942- 2 E. H. HOLMES 2,282,519

PAVEMENT STRUCTURE Filed Dec. 26, 1940 3 Sheets-Sheet l y 9 2- E. H.HOLMES 2,282,519

PAVEMENT STRUCTURE Filed Dec. 26, 1940 3 Sheets-Sheet 2 aa as V w l l=|=l l=| 'INVENTOR E. H. HOLMES PAVEMENT STRUCTURE May 12, 1942.

Filed Dec. 26, 1940 3 Sheets-Sheet 3 Patented May 12, 1942 OFFI E 1PAVEMENT STRUCTURE Edward H. Holmes, Mc KesRocks, Pa.,assignor to FortPitt'Malleable Iron Company, McKees Rocks; Pa.;-a corporation ofPennsylvania Amncatm ne emb 26, 19.4.0; Serial No. 371,663 f 3 Claims.Cl: 94-8) My invention relates to the paving or floor art and moreparticularly to the use of grid-like or grating inserts in paving orfloors, whose main body portion consists of ordinary concrete mixtures,bituminous concrete and other materials put into place while in aplastic condition. The grids are also capable of use inflooring, withoutbeing inset into other pavingmat erial.

One object of my invention is to provide grid inserts of such naturethat they will not only serve to prevent skidding on the pavement orfloor, but which will also serve as reinforcement to bind the mainpavement structure against cracking and spawling, as well as to presenthard wearing areas at the pavement surface.

Another object of my invention is to provide reinforcing grids of suchform that" they can conveniently be installed and embedded in theconcrete or other paving material, orplaced as ,flooring, and whereinthe various grid elements,

are interlocked with one another against relative displacement in anydirection.

Still another object of my invention is to provide an improved manner ofinstalling reinforcing grids in pavements formed of plastic material. v

Briefly stated, my invention comprises the use of metal grids orgratings which usually will be inlaid in the top surface of l apavement, with the upper surfaces of the metal members exposed and withthe various metal membersinterlocked with one another. a

Some of the forms which my invention may take are shown in theaccompanying drawings wherein Figure 1 is a plan view of one of the gridelements entering into a completed structure; Fig. 2 is an end viewthereof taken on the line 11-11 of Fig. 1; Fig. 3 is a View taken on theline IIIIII of Fig. 1; Fig. 4 is a view taken on the line IV-IV of Fig.1, but also indicating the concrete in which the grid is installed; Fig.5 is a sectional view on a reduced scale of an assembly of the gridelements; Fig. 6 is a plan view thereof; Fig. 7 is a schematic view on alarger scale, showing the manner in which the grid elements of Figs. 5and 6 may be brought into interlocking engagement with one another atthe place of installation; Fig. 8 is a plan View showing a modificationof the form of grid shown in Fig. 1, and Fig. 9 is a view taken on theline IXIX of Fig. 8.

Referring first to Figs. 1 to 7, I show metallic grid elements which maysuitably be of malleable iron castings. The grid elements are shown aswhat may be termed full-size elements I!) and ,I2. In the case of ahalf-width only four of these portions I2.

half-size elements II. The half-size are provided in order that thefull-sizev elements III in each row may be placed in offset or staggeredrelation with respect to the elements It of the adjacent rows, thehalf-width elements [I serving to fill in the halfwidth spaces thatwould otherwise be left in certain of the rows, as; shown in Fig. 6. Themat-like structure formed by interlocking of the grid elements may beplaced in a floor or roadway so that the rows of grid elements which areshown in Fig. 6 as extending lengthwise of the drawing usually will belaid crosswise of the roadway or pavement in which the grids are placed.

Each grid comprises bar-like portions I2 that extend lengthwise of thegrid and cross bars I3 that are preferably cast or otherwise formedintegrally with the bars I2. As shown in Fig. 1, each full-size grid haseight bar-like portions grid, there'fare I Each grid also has at itsedges short bar-like projections I4 whose outer ends will abut againstthe outer elements ends of similarly-formed projections on adjacentgrids when the grids are assembled as in Fig. 6.

Each grid I0 has four hooks l5 at one end, with an underlying lip or lugI6 beneath each hook, as shown more clearly in Fig. 3. The half-widthgrids II have only two of these hooks and lips. At its other end, eachgrid has cross bars ll of reduced depth so that when the hooks I5 of anadjacent grid is engaged with the bars II, the

top surfaces of such hooks will be approximately flush with the topsurfaces of the bars I2 and I3.

When the grid structure is to be placed in soft concrete, the concretepaving is laid and, while it is still in a plastic condition, a row ofgrid elements will be installed one-by-one, in interlocked relation. Tothis end, a row of grids is laid preferably crosswise of the pavement,whereupon grids of the next row are placed in position. By tilting thegrids of each row as indicated in Fig. 7, the lugs I6 man be caused topass beneath the end bars I1, so that when the grids of a succeeding roware brought into horizontal alignment with the grids of a preceding row,the grids wil be interlocked with one another, as shown in Fig. 5. Eachgrid II) has interlocked engagement with two grids of the adjacent rowsand each half-width grid II will have interlocking engagement with thefull-width grids III of the adjacent rows, as shown in Fig. 6, so thatthe grids are all interlocked together against displacement inhorizontal directions, the hooks I5 and lugs I6 serving to lock thegrids against relative displacement also in vertical directions.

After a desired number of grids have been assembled to mat form, asshown in Fig. 6, they can be depressed into the concrete-preferably to aplane at which the surface of the concrete is approximately flush withthe tops of the grids. As fast as new concrete is laid and struck off,additional rows of grids will be applied to the preceding rows. The hookconnections of the grids have sufiicient play to permit the grids tofollow a slightly curved contour such as in crowned roadways, bridges,tunnels and even curves of long radius on highways. Such small lumps ormasses of concrete as extend too high above the ribs can be struck offby a straightedge or the like. On certain of the bars I2 1 providefoot-like extensions l9 that will become embedded in the concrete andserve as an anchoring means.

The grids can also-be-utilized in connection with pavements ofbituminous material, in which case they will be placed on a suitablesurface such as some sort of concrete, and thereafter the-asphalt orother bituminous material spread upon and rolled into the grids.

As above stated, the grids serve not only as anti-skid elements, butas-reinforcementfor the paving material, and also as a wear-resistingsurface. Although the concretemay initially be flush with the grids, itwill soon wear down slightly, so that tires of vehicles or the feet ofpedestrianscan have anti-slipping engagement with the bars l2 and i3,evenin the case of factory floors Where grease may occasionally bepresent on the floor. The grids have the further utility in connectionwith asphalt paving, in that theylimit the extent to which the asphalttends to become displaced under traffic when the temperature is warm,the forming of the ridges or depressions that commonly occur in asphaltsurfaces of wide area, since the bars l2 and 13 are sufficiently closetogether to prevent substantial displacement of the asphalt in thismanner. Byway of example, the bars l2 maybe only from one or two inchesapart, while the bars I3 may be only three or fourinches apart. a

In- Figs. 8 and 9 I show a grid structure 20 which may be made infull-width and halfwidth pieces as are the elements 10 and H. In thisarrangement, there is a top plate 2| which almost entirely covers theconcrete and which thus preventing has depending ribs 22 and 23 thatextend lengthwise and crosswise of the grid plate, the grids being alsoprovided with hooks 24 and lugs 25 that correspond to the hooks and lugsl5-l6 and also provided with hook-engaging bars 26. In this arrangementthe plate 2| has upstanding bosses distributed over its top surface, asindicated at 21, that constitute the anti-slipping elements. Holes 28are provided to permit escape of air from beneath the plate 2| when thegrids are being placed in the concrete. It will be understood that whendesired, an anti-slipping surface can be provided by making cut-outsthrough the plate 2|, at the points 21, instead of forming theprotuberances.

I claim as my invention:

1. A pavement structure comprising a body of concrete or the like whichhas inset into its upper surface grid-like members each of which has ahook-engaging bar of reduced depth at one edge and a hook at theopposite edge, with a retaining lug beneath the hook, the hook on eachgrid partially embracing the bar of an adjacent grid and the retaininglug at the hook underlying the bar, whereby the grids are held againstrelative displacement.

2. A pavement structure comprising a body of concrete or the like whichhas inset into its upper surface grid-like members each of which haslongitudinal bars connected by cross bars, to form a grating, hooksformed on the cross bars at one end of each grid member, and the crossbars at the other end being of reduced depth, the hooks on each gridmember having hooked engagement with the reduced bars of an adjacentgrid.

3. A grating structure for use in a flooring, comprising grid-likeelements each having hooks at one edge and retaining. lugs in verticallyspacedrelation to the open sides of the hooks,

and also having'hook-engaging bars at its opposite edge, of reduceddepth relative to the over-all thickness of the grid and each of lessdepth than the space between the adjacent hook and retaining lug, thehooks of each grid being engageable behind the bars of an adjacent gridwhen the grid is tilted to a plane generally perpendicular to the planeof the adjacent grid, and the retaininglugs, the bar and hooks at eachconnection being in superposed relation when the connected grids arebrought to a common plane.

EDWARD H. HOLMES.

